02, A-4 The vents blow hot all the time even when in auto mode. The temp in the car can be lets say 21 and I will have it set at 19, but it still blows hot air. Then I will set it to low and it blows cold. In other word it only blows hot or cold no in between.

 

get someone with vag com to scan your temp control module, it could be a few things, the electric door motor which controls temp or the inside air temp sensor/incoming air temp sensor. A scan will be the best place to start